I’m just under 50,000 miles. 12,000 of that has been towing. Some of the towing could be considered under extreme conditions, through mountain passes and such with over 6000 pounds. As a precaution, I replaced the fluid with the mobil 1 blue label at 42,000 just before the most extreme towing i have done. I also put the larger PML fluid pan in. I haven’t noticed any shudder issues. I do get an occasional hard up shift on light throttle.
I initially thought I had a shudder when towing but it was, lol, driving over raised lane dividing markers. It was when passing so I thought it was caused by acceleration. I was out of state and hadn’t experience them previously. We don’t have those in Missouri.
As a side note, I had some difficulty getting the fluid level right with PML pan. It never slowed to a drip like the GM pan. After a lot of trial and error I think I got it right. Frankly, I wish PML had just duplicated the fill check portion of the GM pan.